A method of the general type in question for controlling delta-T cooking processes is known to one skilled in the art. A description of so-called “delta-T cooking” can be found, for example, at the web sites http://home.tele-net-zh/convotherm/faq.asp and http://hobart.de/kuechentechnik/gartechnik/anwend/braten/htm of the companies Convotherm and Hobart. By this method, the food to be cooked is cooked very carefully in the sense that the difference between the cooking space temperature and the core temperature is maintained at a certain value at all times until the desired set core temperature of the food to be cooked is reached. According to the delta-T cooking method used in the past, therefore, the cooking space temperature is higher than the actual core temperature by the delta-T value. The difference between the actual core temperature and the actual cooking space temperature can be monitored automatically during the cooking time, and a cooking profile can be set up for each type of food to be cooked.
A modification of the delta-T method for use in cooking frozen or deep-frozen products is described in EP 1,445,677 A2.
A method consisting of several phases for cooking meat is described in EP 0,723,115 A2. To carry out this method, a cook specifies a desired cooking time and a desired final temperature of the cooked food. In a first, optional, grilling phase, the cooking space temperature is brought to a value of approximately 250° C. and held automatically at this value. Then the cooking space temperature is lowered to a second value, which is slightly above the final desired temperature of the food being cooked. As soon as the temperature of the food being cooked is within 15° C. of the desired final temperature, the cooking space temperature is no longer regulated, and instead the temperature of the food being cooked is regulated, namely, in such a way that it increases linearly with time and reaches the desired end value precisely at the end of the cooking time.
A method for controlling a cooking process in which a cooking process sensor takes into account the cooking kinetics of the food item to be cooked is known from DE 199 45 021 A1.
In general, the very careful delta-T cooking method has a very positive effect both on products which require only a very short cooking time and on those which require a very long cooking time. Nevertheless, unsatisfactory sensory results are still obtained regularly when the item to be cooked is of large diameter, when a relatively large delta-T value is maintained, or when large amounts are being cooked at once. It has been found, however, that, even when the cooking space temperature is lowered to the set core temperature, as soon as the set core temperature of the food is reached, the food product can still be overcooked and suffer an unnecessary loss of weight, juiciness, and color.